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Physicist Ashoke Sen became the first Indian physicist to be awarded the Oskar Klein Medal for his work in string theory.

About Oskar Klein Medal

  • Instituting Bodies: Awarded annually by Stockholm University jointly with the Nobel Committee for Physics of the Royal Swedish Academy of Sciences.

  • Origins: Established in 1988 to honor the scientific legacy of Oskar Klein, an eminent Swedish theoretical physicist.

  • Core Purpose: Recognizes distinguished international contributions to theoretical physics.  

  • Commemorative Lecture: The recipient is invited to deliver the official Oskar Klein Memorial Lecture at Stockholm University.

  • Past Laureates: First three recipients were Nobel laureates Chen-Ning Yang (1988), Steven Weinberg (1989), and Hans Bethe (1990), joined over the years by physics icons such as Stephen Hawking (2003), Peter Higgs (2009), and Kip Thorne (2016).

2026 Winner and Contributions

  • Winner: Professor Ashoke Sen, ICTS-Infosys Madhava Chair Professor at the International Centre for Theoretical Sciences (ICTS-TIFR) in Bengaluru, a center under the Tata Institute of Fundamental Research (TIFR) within the Department of Atomic Energy (DAE).

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  • Historic Milestone: He is the first Indian physicist to receive the Oskar Klein Medal in its 38-year history.

  • Key Scientific Contributions:

    • S-Duality: Mathematically proved that a system at strong interaction strength (coupling) is equivalent to a dual system at weak coupling, making previously intractable calculations solvable.

    • Unification of String Theories: Showed that five distinct string theories previously treated as separate are actually different limits of a single underlying master theory.

    • Black Hole Microstate Entropy Counting: Developed precise quantum counting of microscopic states to provide physical grounding for the macroscopic Bekenstein-Hawking formula.

    • String Field Theory & Tachyon Condensation: Formulated String Field Theory to describe quantum string dynamics and proposed the Sen conjecture on open string tachyon condensation regarding unstable D-branes.

  • Major Recognitions: Breakthrough Prize in Fundamental Physics (2012), Dirac Medal (2014), Fellow of the Royal Society (1998), Shanti Swarup Bhatnagar Prize (1994), Padma Shri (2001), and Padma Bhushan (2013).

What is String Theory?

It is a theoretical framework proposing that the fundamental constituents of nature are tiny, vibrating one-dimensional strings rather than zero-dimensional point particles.

  • Objective: Serves as a leading candidate for a quantum theory of gravity, aiming to unify general relativity (gravitational interactions) with quantum mechanics (subatomic particle interactions).

  • Physical Mechanism: Different vibrational modes and frequencies of a string manifest as different elementary particles and fundamental forces in the universe.

Source: INDIANEXPRESS

PRACTICE QUESTION

Q. Who became the first Indian physicist to be awarded the Oskar Klein Medal in 2026?

(A) Jayant Narlikar

(B) Ashoke Sen

(C) Thanu Padmanabhan

(D) Abhay Ashtekar

Answer: B

Explanation:

Physicist Ashoke Sen became the first Indian physicist to be awarded the Oskar Klein Medal in 2026 for his pioneering work in string theory. The award is presented annually by Stockholm University and the Nobel Committee for Physics.